dbwrap: Add dbwrap_do_locked

With a proper implementation this enables modifications without
having to allocate a record. In really performance sensitive code
paths this matters.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>

3 files changed, 45 insertions, 0 deletions

diff --git a/lib/dbwrap/dbwrap.c b/lib/dbwrap/dbwrap.c
index 260a977f927..22437f62083 100644
--- a/lib/dbwrap/dbwrap.c
+++ b/lib/dbwrap/dbwrap.c
@@ -498,6 +498,42 @@ NTSTATUS dbwrap_parse_record_recv(struct tevent_req *req)
 	return tevent_req_simple_recv_ntstatus(req);
 }
 
+NTSTATUS dbwrap_do_locked(struct db_context *db, TDB_DATA key,
+			  void (*fn)(struct db_record *rec,
+				     void *private_data),
+			  void *private_data)
+{
+	struct db_record *rec;
+
+	if (db->do_locked != NULL) {
+		struct db_context **lockptr;
+		NTSTATUS status;
+
+		if (db->lock_order != DBWRAP_LOCK_ORDER_NONE) {
+			dbwrap_lock_order_lock(db, &lockptr);
+		}
+
+		status = db->do_locked(db, key, fn, private_data);
+
+		if (db->lock_order != DBWRAP_LOCK_ORDER_NONE) {
+			dbwrap_lock_order_unlock(db, lockptr);
+		}
+
+		return status;
+	}
+
+	rec = dbwrap_fetch_locked(db, db, key);
+	if (rec == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	fn(rec, private_data);
+
+	TALLOC_FREE(rec);
+
+	return NT_STATUS_OK;
+}
+
 int dbwrap_wipe(struct db_context *db)
 {
 	if (db->wipe == NULL) {
diff --git a/lib/dbwrap/dbwrap.h b/lib/dbwrap/dbwrap.h
index 04e179e75e6..1161bf0a493 100644
--- a/lib/dbwrap/dbwrap.h
+++ b/lib/dbwrap/dbwrap.h
@@ -83,6 +83,11 @@ struct db_record *dbwrap_try_fetch_locked(struct db_context *db,
 					  TDB_DATA key);
 struct db_context *dbwrap_record_get_db(struct db_record *rec);
 
+NTSTATUS dbwrap_do_locked(struct db_context *db, TDB_DATA key,
+			  void (*fn)(struct db_record *rec,
+				     void *private_data),
+			  void *private_data);
+
 NTSTATUS dbwrap_delete(struct db_context *db, TDB_DATA key);
 NTSTATUS dbwrap_store(struct db_context *db, TDB_DATA key,
 		      TDB_DATA data, int flags);
diff --git a/lib/dbwrap/dbwrap_private.h b/lib/dbwrap/dbwrap_private.h
index 2858afd8539..e757215d389 100644
--- a/lib/dbwrap/dbwrap_private.h
+++ b/lib/dbwrap/dbwrap_private.h
@@ -68,6 +68,10 @@ struct db_context {
 		void *private_data,
 		enum dbwrap_req_state *req_state);
 	NTSTATUS (*parse_record_recv)(struct tevent_req *req);
+	NTSTATUS (*do_locked)(struct db_context *db, TDB_DATA key,
+			      void (*fn)(struct db_record *rec,
+					 void *private_data),
+			      void *private_data);
 	int (*exists)(struct db_context *db,TDB_DATA key);
 	int (*wipe)(struct db_context *db);
 	int (*check)(struct db_context *db);